adding bootstrap

Author: springframeworkguru

src/main/java/guru/springframework/spring6webapp/bootstrap/BootstrapData.java

@@ -0,0 +1,67 @@
+package guru.springframework.spring6webapp.bootstrap;
+
+import guru.springframework.spring6webapp.domain.Author;
+import guru.springframework.spring6webapp.domain.Book;
+import guru.springframework.spring6webapp.repositories.AuthorRepository;
+import guru.springframework.spring6webapp.repositories.BookRepository;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.stereotype.Component;
+
+/**
+ * Created by jt, Spring Framework Guru.
+ */
+@Component
+public class BootstrapData implements CommandLineRunner {
+
+    private final AuthorRepository authorRepository;
+    private final BookRepository bookRepository;
+
+    public BootstrapData(AuthorRepository authorRepository, BookRepository bookRepository) {
+        this.authorRepository = authorRepository;
+        this.bookRepository = bookRepository;
+    }
+
+    @Override
+    public void run(String... args) throws Exception {
+        Author eric = new Author();
+        eric.setFirstName("Eric");
+        eric.setLastName("Evans");
+
+        Book ddd = new Book();
+        ddd.setTitle("Domain Driven Design");
+        ddd.setIsbn("123456");
+
+        Author ericSaved = authorRepository.save(eric);
+        Book dddSaved = bookRepository.save(ddd);
+
+        Author rod = new Author();
+        rod.setFirstName("Rod");
+        rod.setLastName("Johnson");
+
+        Book noEJB = new Book();
+        noEJB.setTitle("J2EE Development without EJB");
+        noEJB.setIsbn("54757585");
+
+        Author rodSaved = authorRepository.save(rod);
+        Book noEJBSaved = bookRepository.save(noEJB);
+
+        ericSaved.getBooks().add(dddSaved);
+        rodSaved.getBooks().add(noEJBSaved);
+
+        System.out.println("In Bootstrap");
+        System.out.println("Author Count: " + authorRepository.count());
+        System.out.println("Book Count: " + bookRepository.count());
+
+
+    }
+}
+
+
+
+
+
+
+
+
+
+

src/main/java/guru/springframework/spring6webapp/domain/Author.java

@@ -2,6 +2,7 @@
 
 import jakarta.persistence.*;
 
+import java.util.HashSet;
 import java.util.Set;
 
 /**
@@ -17,7 +18,7 @@ public class Author {
     private String lastName;
 
     @ManyToMany(mappedBy = "authors")
-    private Set<Book> books;
+    private Set<Book> books = new HashSet<>();
 
     public Set<Book> getBooks() {
         return books;

src/main/java/guru/springframework/spring6webapp/domain/Book.java

@@ -2,6 +2,7 @@
 
 import jakarta.persistence.*;
 
+import java.util.HashSet;
 import java.util.Set;
 
 /**
@@ -19,7 +20,7 @@ public class Book {
     @ManyToMany
     @JoinTable(name = "author_book", joinColumns = @JoinColumn(name = "book_id"),
         inverseJoinColumns = @JoinColumn(name = "author_id"))
-    private Set<Author> authors;
+    private Set<Author> authors = new HashSet<>();
 
     public Set<Author> getAuthors() {
         return authors;